1. Field of the Invention
The present invention is generally related to a mounting system for a marine engine and, more particularly, to a mounting system for a four cylinder in-line engine that is tilted, or slanted, within the structure of a marine vessel.
2. Description of the Related Art
Those skilled in the art of marine propulsion systems are aware of various different methods for supporting an engine in relation to a marine drive unit, such as a sterndrive device. These support techniques typically involve a plurality of mounts which attach the marine engine to the marine vessel. The mounts typically comprise a metallic structure that is combined with an elastomeric material for the purpose of supporting the marine engine in such a way that vibrations are damped and prevented from being transmitted directly to the marine vessel structure.
U.S. Pat. No. 3,722,456, which issued to Lambrecht et al. on Mar. 27, 1973, describes a sterndrive unit propeller trimming arrangement. The system comprises a boat hull and a sterndrive unit which includes and is supported by an engine and which further includes a marine propulsion lower unit tiltable vertically and swingable horizontally independently of the engine, together with means mounting the sterndrive unit on the boat hull including means for selectively vertically displacing or tilting the forward end of the engine relative to the rear of the engine.
U.S. Pat. No. 3,929,089, which issued to Lambrecht et al. on Dec. 30, 1975, describes a sterndrive hydraulic trim control system including a tilt position indicator. The unit includes a sterndrive leg fixed to the rear of an engine and including a part which is tiltable vertically and swingable horizontally independently of the engine. It includes a rearwardly located elastomeric mount connected to the sterndrive unit and adapted for connection to a boat hull for vibrationally isolating and supporting the sterndrive unit from the boat hull. It also provides a pivotal axis relative to which the sterndrive unit is tiltable relative to the boat hull, an elastomeric part, a bracket fixed to the elastomeric part and adapted to be fixed to the boat hull, an arm fixed to the elastomeric part remotely from the bracket, and a jacking mechanism connected between the engine and the arm for tilting the sterndrive unit relative to the boat hull while also supporting and vibrationally isolating the engine from the boat hull.
U.S. Pat. No. 5,129,479, which issued to Fujii et al. on Jul. 14, 1992, describes a suspension system for an engine and transmission assembly mounted transversely in a vehicle. It has a main axis of moment of inertia extending in a left and right direction of the vehicle, a single first mount located at a first end of the engine and transmission assembly and at least one additional mount located in the vicinity of an opposite second end of the assembly. The center of gravity of the assembly is located on a main axis of moment of inertia of the assembly extending between the first and second ends and is closer to the first end than to the second end.
U.S. Pat. No. 5,450,922, which issued to Doi et al. on Sep. 19, 1995, describes an automobile power plant mounting structure. The power plant is mounted on both sides in a transverse direction by mounts. Each of the mounts is placed within a triangle defined by a point on a primary inertial axis of the power plant on the transverse side of the power plant.
U.S. Pat. No. 5,478,264, which issued to Law on Dec. 26, 1995, describes a marine engine mounting system which includes a vibration absorbing assembly for mounting a marine engine to a stringer. It includes a mounting bracket adapted for attachment to the marine engine, a base adapted for attachment to a stringer, and first and second resilient vibration absorbing members supported within the mounting bracket and selectively connected to the base. The first resilient member is relatively more resistant in a horizontal direction for cushioning horizontal thrust loads acting upon the bracket with respect to the base.
U.S. Pat. No. 5,634,832, which issued to Nakase et al. on Jun. 3, 1997, describes an induction system for a four-cycle watercraft engine. Various induction system configurations adapt a four-cycle multi-cylinder engine for use in small personal watercrafts. This is accomplished by canting the engine at an angle to a vertically extending plane and positioning the induction system on the upper portion of the cylinder head.
U.S. Pat. No. 6,027,384, which issued to Nitta et al. on Feb. 22, 2000, describes a four-cycle engine for a small jet boat. The engine is provided which is suitable for use in a vehicle or an apparatus such as a small jet boat to be operated on the premise that it often overturns. An oil pan is disposed below the bottom of a crankcase, the spaces and the components are communicated with each other via a communicating hole which is formed in the bottom of the crankcase.
U.S. Pat. No. 6,386,309, which issued to Park on May 14, 2002, describes a mount assembly for an automotive power plant. The mounting structure for a vehicle includes an engine side mount assembly, a transmission side mount assembly, and front and rear mount assemblies. The engine side mount assembly includes a mount which is less stiff in the front and rear directions than in the upward and downward directions of the vehicle and is arranged such that an axis of the mount is parallel to an inertial axis of a moment of inertia of the power plant.
U.S. Pat. No. 6,390,863, which issued to Imanaga on May 21, 2002, describes an outboard motor which includes an engine holder, an engine disposed above the engine holder in a state wherein the outboard motor is mounted to a hull, a mount unit including upper and lower mount devices for mounting the outboard motor to the hull and a bracket through which the upper and lower mount devices are mounted to the hole.
U.S. Pat. No. 6,415,884, which issued to Hawener et al. on Jul. 9, 2002, describes a suspension system for a drive assembly of a motor vehicle. The drive assembly is secured above a subframe to a separate cross member by way of two engine mounts, with a third mount being provided on a transmission housing or on a distributor drive. The cross member is secured separately and rigidly to the subframe at the vehicle body.
U.S. Pat. No. 6,645,019, which issued to Shiomi et al. on Nov. 11, 2003, describes an outboard engine system. An inertia force generated longitudinally by a piston is countervailed by an inertia force generated by a crankshaft and inertia forces laterally generated vibrate a body of the outboard engine system laterally about a phantom center point of vibration. An elastomeric member resiliently supporting the system body on a hull has a rigidity in a tangent direction about the phantom center point of vibration.
U.S. Pat. No. 7,014,519, which issued to Batten et al. on Mar. 21, 2006, discloses a marine propulsion system with a tilted in-line engine. The engine is disposed at a tilted angle relative to a vertical plane in order to reduce the maximum height requirement space of an engine compartment of a marine vessel. The crankshaft axis of the in-line engine can be located on a vertical vessel symmetry plane or can be offset from it. The crankshaft of the in-line engine can be disposed parallel to the vessel symmetry plane, within the vessel symmetry plane, or perpendicular to the vessel symmetry plane.
The patents described above are hereby expressly incorporated by reference in the description of the present invention.